Hi Herbert,
Thanks a lot for your review!
On 10/4/22 13:52, Herbert Xu wrote:
> On Tue, Oct 04, 2022 at 04:49:12AM +0000, Taehee Yoo wrote:
>>
>> #define ECB_WALK_START(req, bsize, fpu_blocks) do { \
>> void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); \
>> + unsigned int walked_bytes = 0; \
>> const int __bsize = (bsize); \
>> struct skcipher_walk walk; \
>> - int err = skcipher_walk_virt(&walk, (req), false); \
>> + int err; \
>> + \
>> + err = skcipher_walk_virt(&walk, (req), false); \
>> while (walk.nbytes > 0) { \
>> - unsigned int nbytes = walk.nbytes; \
>> - bool do_fpu = (fpu_blocks) != -1 && \
>> - nbytes >= (fpu_blocks) * __bsize; \
>> const u8 *src = walk.src.virt.addr; \
>> - u8 *dst = walk.dst.virt.addr; \
>> u8 __maybe_unused buf[(bsize)]; \
>> - if (do_fpu) kernel_fpu_begin()
>> + u8 *dst = walk.dst.virt.addr; \
>> + unsigned int nbytes; \
>> + bool do_fpu; \
>> + \
>> + if (walk.nbytes - walked_bytes > ECB_CBC_WALK_MAX) { \
>> + nbytes = ECB_CBC_WALK_MAX; \
>> + walked_bytes += ECB_CBC_WALK_MAX; \
>> + } else { \
>> + nbytes = walk.nbytes - walked_bytes; \
>> + walked_bytes = walk.nbytes; \
>> + } \
>> + \
>> + do_fpu = (fpu_blocks) != -1 && \
>> + nbytes >= (fpu_blocks) * __bsize; \
>> + if (do_fpu) \
>> + kernel_fpu_begin()
>>
>> #define CBC_WALK_START(req, bsize, fpu_blocks) \
>> ECB_WALK_START(req, bsize, fpu_blocks)
>> @@ -65,8 +81,12 @@
>> } while (0)
>>
>> #define ECB_WALK_END() \
>> - if (do_fpu) kernel_fpu_end(); \
>> + if (do_fpu) \
>> + kernel_fpu_end(); \
>> + if (walked_bytes < walk.nbytes) \
>> + continue; \
>> err = skcipher_walk_done(&walk, nbytes); \
>> + walked_bytes = 0; \
>> } \
>> return err; \
>> } while (0)
>
> skcipher_walk_* is supposed to return at most a page. Why is this
> necessary?
>
> Cheers,
I referred to below link.
https://lore.kernel.org/all/MW5PR84MB18426EBBA3303770A8BC0BDFAB759@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
Sorry for that I didn't check that skcipher_walk_* returns only under 4K
sizes.
So, I thought fpu context would be too long.
But, I just checked the skcipher_walk_*, and it's right, it returns
under 4K sizes.
So, there are no problems as you mentioned.
Thank you so much!
Taehee Yoo
